This invention relates to a disposable diaper adapted to absorb and contain body wastes.
Such a diaper is usually provided along the end flaps defining the waist band region with elastic members so that contraction of these elastic members may function to press the diaper against a wearer""s skin and thereby prevent the diaper from getting out of shape or from slipping down during use. Consequently, perspiration occurs along the region of the wearer""s skin against which the end flaps are pressed. Such oppression and perspiration give the wearer an unpleasant feeling and may cause various skin diseases such as eczema, eruption and heat rash.
To overcome this adverse affection of perspiration, it is well known, for example, from Japanese Utility Model Application Disclosure Gazette (Kokai) No. Hei5-41535 to detachably attach a sweat-absorbent sheet of cotton cloth to the inner surface of the rear waist region.
The Japanese Utility Model Application Disclosure Gazette (Kokai) No. Hei5-41525 discloses providing the rear waist band region with a sweat-absorbent sheet of cotton cloth. However, it is difficult for such a diaper to avoid the unpleasant feeling and skin diseases merely by providing a sweat-absorbent sheet, because it has been found that the waist band region of the diaper should be sweat-absorbent and, at the same time, sufficiently breathable to avoid such problems.
It is an object of this invention to compose at least one of the end flaps in the front and rear waist regions defining the waist band region in such a manner that the end flap may have not only a ventilating function but also a sweat-absorbing function.
According to this invention, there is provided a disposable diaper having a front waist region, a rear waist region and a crotch region, the diaper comprising an absorbent unit including a liquid-pervious topsheet, a liquid-impervious backsheet and a liquid-absorbent core disposed between the topsheet and the backsheet, said backsheet including a breathable outer layer and a liquid-impervious inner layer laminated with an inner surface of said breathable outer layer, and, in said front and rear waist regions, a pair of end flaps extending outward beyond longitudinally opposite ends of said absorbent core.
In such a disposable diaper, at least one of the end flaps in said front and rear waist regions includes a region having a predetermined dimension defined between a longitudinal end of the end flap and the longitudinal end of the absorbent core adjacent to the longitudinal end of the end flap, the region having the predetermined dimension is formed by portions of the breathable outer layer and the liquid-pervious topsheet that extend outward beyond the longitudinal end of the absorbent core and further being provided on an inner surface thereof with a breathable sweat-absorbent sheet bonded thereto so as to cover the region having the predetermined dimension.
This invention includes alternative embodiments wherein the breathable sweat-absorbent sheet contains at least 20% by weight of hydrophilic fibers; wherein the breathable sweat-absorbent sheet comprises a laminate having an upper layer containing at least 20% by weight of hydrophilic fibers and is intended to. come in contact with a wearer""s skin and a lower layer formed from hydrophobic fibers which is intended not to come in contact with the wearer""s skin; wherein the breathable sweat-absorbent sheet has a plurality of pores each having a diameter of 0.1xcx9c3 mm; wherein the breathable sweat-absorbent sheet is bonded to the end flap intermittently at least in a circumferential direction of the diaper; the end flap having the breathable sweat-absorbent sheet bonded thereto is provided with elastic members adapted to be stretchable and contractable in the circumferential direction of the diaper; and the outer layer of the backsheet is formed from a nonwoven fabric and the inner layer of the backsheet is formed from a plastic film.